Orchid propagation allows enthusiasts to expand their collection, share plants, and potentially save a struggling parent plant.
Understanding Orchid Growth Habits
Orchids exhibit two primary growth habits: monopodial and sympodial, which dictate the most suitable propagation method. Monopodial orchids, such as Phalaenopsis and Vanda, grow vertically from a single stem, continuously adding new leaves from the apex. They do not possess pseudobulbs for water and nutrient storage, relying instead on their succulent leaves and roots. These orchids are known to produce plantlets called keikis.
Sympodial orchids, including Cattleya, Cymbidium, Oncidium, and most Dendrobiums, grow horizontally, developing new shoots from a creeping rhizome. These new growths often form pseudobulbs, which are thickened stems that store water and nutrients, enabling the plant to endure drier periods. This growth pattern makes sympodial orchids ideal candidates for propagation by division.
Propagating Orchids by Division
Dividing sympodial orchids is typically performed after the flowering period, when new growth begins. Avoid dividing plants when new spikes or blooms are forming, as this can disrupt their development. This method is useful when an orchid has outgrown its pot or its potting medium has deteriorated.
Before beginning, gather:
Sterilized cutting tools (razor blade, sharp knife, or pruners)
New pots and fresh orchid potting mix
Cinnamon or charcoal powder to seal cut surfaces
Carefully remove the orchid from its current pot, gently untangling the roots and clearing away old potting material.
Identify natural divisions, ensuring each new section has at least three to five pseudobulbs. Larger divisions generally result in healthier new plants. Sterilize your cutting tool between cuts to prevent disease transmission. Make clean cuts through the rhizome to separate the divisions.
Apply cinnamon powder or charcoal to all cut surfaces on both the parent plant and new divisions to act as a natural fungicide. Pot each division into an appropriately sized pot with fresh, well-draining orchid mix, ensuring the new growth is at surface level.
Propagating Orchids from Keikis
Keikis, Hawaiian for “baby,” are small plantlets that develop on the flower spike or sometimes the stem of an orchid. They are genetically identical clones of the parent plant. Phalaenopsis and Dendrobium orchids are among the varieties most prone to forming keikis.
A keiki is ready for removal when it has developed at least two to three leaves and roots that are 1 to 3 inches long. Removing a keiki too early, especially without sufficient roots, can reduce its chances of survival. Use sterilized cutting tools, such as a sharp razor blade or gardening shears, to make the separation.
To remove a keiki, cut the flower spike or stem about 1 to 2 inches above and below where the keiki is attached, taking care not to damage its roots. Apply cinnamon powder to the cut ends of both the keiki and the mother plant to prevent fungal infections. Pot the keiki into its own small, 4-inch pot, using a fine-grade orchid potting mix like sphagnum moss or fine bark. Ensure the potting medium is damp but not waterlogged, and provide initial support if needed to keep the young plant upright.
Caring for New Orchid Propagations
Newly propagated orchid plants require specific care. Immediately after potting, place new divisions or keikis in an area that receives bright, indirect light, avoiding direct sun exposure which can scorch new foliage. Gradually increase light exposure as the plant develops.
Watering needs for young propagations require the potting mix to be kept consistently moist but never waterlogged to prevent root rot. High humidity is beneficial for encouraging new root growth and plant vigor. Maintaining stable, warm temperatures, between 70°F and 80°F during the day, will also support their development.
Delay heavy fertilization until new growth is established and new roots have appeared. If fertilization is necessary, use a dilute solution, about half the recommended strength, every two to four weeks. Providing these conditions will help the young orchid thrive and mature.
Troubleshooting Common Propagation Issues
Despite careful propagation, new orchids can encounter problems that hinder growth. If a new propagation shows no growth or stunted growth, causes include insufficient light, improper watering, or stress from propagation. Ensure the plant receives sufficient indirect light and re-evaluate watering practices to balance moisture levels.
Root or stem rot indicates overwatering, poor drainage, or fungal issues. If roots appear mushy, brown, or black, unpot the plant, trim away affected areas with sterilized tools, and repot into fresh, well-draining media. Yellowing or dropping leaves can signal either over or under-watering, or shock. Check the moisture level of the potting mix and the health of the roots to determine the cause.
For keikis not developing roots, lack of humidity or insufficient maturity before removal are factors. Increase ambient humidity around the keiki and ensure it met the minimum root and leaf criteria before separation. Addressing these issues promptly can help salvage a struggling propagation.